WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now

Evaluate log 18 + log6 - log16\(^{\frac{1}{2}}\)

Mathematics
NECO 2005

Evaluate log 18 + log6 - log16\(^{\frac{1}{2}}\)

  • A. log 3
  • B. log 9
  • C. log 20
  • D. 3 log 2
  • E. 3 log 3
WAEC offline past questions - with all answers and explanations in one app - Download for free
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
Correct Answer: Option E
Explanation

To evaluate the expression \( \log 18 + \log 6 - \log 16^{\frac{1}{2}} \), we can use the properties of logarithms.

Simplify \( \log 16^{\frac{1}{2}} \)

Using the power rule of logarithms: \(\log 16^{\frac{1}{2}} = \frac{1}{2} \log 16\)

Substitute back into the expression:

Now rewrite the expression: \(\log 18 + \log 6 - \frac{1}{2} \log 16\)

Combine the logarithms:

Using the product property of logarithms: \(\log 18 + \log 6 = \log (18 \cdot 6) = \log 108\)

So we can rewrite the expression as: \(\log 108 - \frac{1}{2} \log 16\)

 Rewrite \( \frac{1}{2} \log 16\)

Using the power rule again: \(\frac{1}{2} \log 16 = \log 16^{\frac{1}{2}} = \log 4\)

Substitute back;

Now we have: \(\log 108 - \log 4\)

Using the quotient property of logarithms:  \(\log \left( \frac{108}{4} \right)\)

Simplify \(\frac{108}{4}\)

Calculating: \(\frac{108}{4}\) = 27

Thus, the expression simplifies to: log 27 = 3log3

NOTE: all is in base 10.


Report an Error Ask A Question Download App
Post UTME Past Questions Agent
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
WAEC offline past questions - with all answers and explanations in one app - Download for free

Contributions ({{ comment_count }})

Please wait...

{{ settings.no_comment_msg ? settings.no_comment_msg : 'There are no comments' }}

Quick Questions

Post your Contribution

Please don't post or ask to join a "Group" or "Whatsapp Group" as a comment. It will be deleted. To join or start a group, please click here

{{ quote.posted_by.display_name }}
{{ settings.form_textarea_description }}
 
Post UTME Past Questions Agent
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
WAEC offline past questions - with all answers and explanations in one app - Download for free
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
WAEC Past Questions, Objective & Theory, Study 100% offline, Download app now - 127076
Post-UTME Past Questions - Original materials are available here - Download PDF for your school of choice + 1 year SMS alerts
WAEC and NECO CBT Software for Computers and Laptops - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now
WAEC and NECO CBT App for Mobile Devices - Candidates, Schools, Centres, Resellers - 100% Offline -Download Now